1. Field of the Invention
The present invention relates to an in-the-ear hearing aid of which the battery housing section is provided with a waterproof construction.
2. Description of the Prior Art
In a conventional in-the-ear hearing aid provided with a waterproof construction, a battery housing section provided with a waterproof construction is known in which a rotatable battery holder is opened to allow the battery holder to hold a button type air battery and then, the battery holder is closed to house the button type air battery. The battery holder is composed of a battery holder core and an elastic cover member adapted to cover the battery holder and to cover and hold the button type air battery. When the battery holder is closed, the elastic cover member is compressively inserted between an opening section of a face plate and the battery holder core to serve as a packing (for example, refer to Patent Document 1).    Patent Document 1: Japanese Patent Application Publication No. 2004-227980
However, in the in-the-ear hearing aid disclosed in Patent Document 1, although the waterproof construction is provided at a contact section between a lid section of the battery holder and a surface of the face plate, a battery housing space communicates with an inner shell space because no partition is provided therebetween. Thus, there is a possibility that moisture such as sweat and water may infiltrate into the battery housing section when the battery holder is open. There is also a possibility that the moisture which has infiltrated into the battery housing section will run through battery contacting units to corrode a soldered section of electric parts disposed in the inner shell space.